Woodward’s synthesis of vitamin B<Subscript>12</Subscript>

The synthesis of this molecule was a landmark in organic synthesis. It involved the masterful control of shapes of molecules to create 9 chiral centres with known absolute and relative configurations. The concepts of absolute and induced asymmetric synthesis are here explained.     

"David Copperfield": Perfect Reflection of Dickens'''' Creative Ideas

Charles Dickens（1812—1870）was the most popular and internationally known as an Engilsh novelist. Being the greatest representative of the English critical realism, he gives us a most vivid picture of the everyday life of the ordinary people of his time. He created a large number of characters , well drawn, full of life and unforgettable.He has suffered so bitterly himself as a child and had seen so much evil that he burned with the desire to fight it to the end .While presenting a truthfu…     

‘Content’ versus ‘style’: Acquiescence in student evaluation of teaching?

Structural equation modelling is used to measure the existence of a response style (in particular, acquiescence) behind three balanced Likert scales measuring different concepts in a questionnaire for student evaluation of teaching in higher education. Exploration with one sample (n = 1125) and confirmation in a second sample (n = 710) from a different population (different students, different courses) shows the existence of a common factor behind these scales. However, the weak correlation with the variable ‘sum of agreements’ does not support the idea of acquiescence in student evaluation of teaching. Instead, the common factor could be interpreted as a halo factor influencing different scales in the questionnaire. The implications of this exploratory study for future research on acquiescence in student evaluations of teaching are discussed.     

ce.Tradition; Poem; History; Fancy0四川职业技术学院学报Journal of Si

ocational and Technical College50-52I5F082;4;F;H;F082_4;王光碧;00020009;44-46人性的悲剧美,悲剧的人性美——解读《平凡的世界》的     

The Child is Father of the Man——诗歌&#183;变异&#183;翻译

诗歌,是语言最集中、最精练的文学作品的一种样式,也是最高的文学形式.它是语言的艺术,有其自身的特点.尤其是词汇和句法的独特之处,也就是对常规来说的变异,更是诗歌的一大特色.也正是这种对常规的暴力的变异,成了读懂诗歌、欣赏诗歌的"拦路虎",更是诗歌翻译的"克星",甚至造成诗歌某种程度上的"不可译".本文将着手于语义变异和书写变异在诗歌中的运用,并探求这种诗歌的翻译.     

Is editing the roadblock to the internationalization of Chinese academic journals?

“China’s internationalization” is in part realized through the dissemination of Chinese publications, such as academic journals. Therefore, editorial proficiency in the English language is of vital importance to the quality of the journals. This article analyzes the results of the two projects sponsored by the General Administration of Press and Publication of the People’s Republic of China in 2007 and 2010 respectively, namely the “Analytical Evaluation of Language and Editing Quality of Chinese Academic Journals in English Language Issued in 2006”, and the “Evaluation of Publication Quality of the China-Grown English Periodicals Issued in 2009, Sanctioned from 2005 to 2009”, and proposes solutions to the problems presented therein.     

Syntheses and characterizations of alloyed Co<Subscript><Emphasis Type="Italic">x</Emphasis></Subscript>Ni<Subscript>1−<Emphasis Type="Italic">x</Emphasis></Subscript>O nanocrystals

Alloying is an effective way to manipulate the composition and physico-chemical properties of functional materials. We demonstrated the syntheses of alloyed Co _x Ni_1?x O nanocrystals using a nonaqueous approach, with x continuously tuned from 0 to 1 by varying the molar ratios of the cobalt precursor in the reagents. The morphological, structural, and compositional properties of the alloyed Co _x Ni_1?x O nanocrystals were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), inductively coupled plasma atomic emission spectroscopy (ICP-AES), and energy dispersive X-ray spectroscopy (EDS). The results showed that the cobalt and nickel atoms were homogeneously distributed in the alloyed nanocrystals. The as-prepared Co _x Ni_1?x O nanocrystals can be applied as the hole-transporting layers in polymer light emitting diodes (PLEDs). Our study provides a good example for the syntheses of alloyed oxide nanocrystals with continuously tunable composition.     

(Re)location of Home in Louise Erdrich’s <Emphasis Type="Italic">The Game of Silence</Emphasis>

Louise Erdrich is one of the most influential writers of the Native American Renaissance. Her contributions to the representation of Native American history have been great, and her masterpieces of children’s literature have won her a prominent reputation. This article explores the (re)location of the concept of home in Erdrich’s The Game of Silence and analyzes the novel’s historical context with reference to various discourses on space/place, including those by Native Americans. Erdrich’s narration reconstructs a space for Native American culture, religion and tradition, and for the continued survival of Native American people. She represents the silent history of her ancestors’ displacement to the West, as white settlers encroached upon their beloved homeland. As Erdrich’s work so poignantly illustrates, for Native American people, home is nowhere and anywhere.     

Inclusion or exclusion?: A narrative inquiry of a language teacher’s identity experience in the ‘new work order’ of competing pedagogies

This paper investigates how an EFL teacher negotiates her identity to adapt to the ‘new work order’ in an English education department at a university in China. From a narrative inquiry perspective, it aims to illuminate the complexity of teacher identity in the context of a reform where teachers must reconcile conflicting selves in order to contend with a workplace in which liberal and traditional pedagogies coexist. The findings show that teachers need to shift their identities to survive change. Exclusion from the workplace community of practice can be seen as an alternative form of participation in the reform practices.     

Enhancing Prospective Teachers’ Knowledge of Learners’ Intuitive Conceptions: The Case of <Emphasis Type="Italic">Same A</Emphasis>–<Emphasis Type="Italic">Same B</Emphasis>

This paper addresses the accumulating knowledge of prospective teachers of secondary school mathematics and their acquired proficiency during the course “Psychological aspects of mathematics education,” in which we discussed theoretical models including the intuitive rules theory. Participants’ performances are examined by means of an extensive report of two episodes, one during the course and one afterwards. These episodes marked different stages in the prospective teachers’ analysis of their own and of students’ solutions, which led me to conclude that exposing prospective teachers to the intuitive rules theory is important, since their familiarity with the theory provided them with a tool to reflect on their own mathematical solutions (subject matter knowledge; SMK), on others’ solutions, and on the tasks (pedagogical content knowledge; PCK).     

A Story of Leonardo Da Vinci 达&#183;芬奇的故事

莱昂纳多&#183;达&#183;芬奇(1452-1519)是欧洲文艺复兴时期意大利的—位卓越的国家。他以《蒙娜丽莎》和《最后的晚餐》而著名。     

Optimal multi-degree reduction of Bézier curves with <Emphasis Type="Italic">G</Emphasis><Superscript>1</Superscript>-continuity

This paper presents a novel approach to consider optimal multi-degree reduction of Bézier curve with G¹-continuity. By minimizing the distances between corresponding control points of the two curves through degree raising, optimal approximation is achieved. In contrast to traditional methods, which typically consider the components of the curve separately, we use geometric information on the curve to generate the degree reduction. So positions and tangents are preserved at the two endpoints. For satisfying the solvability condition, we propose another improved algorithm based on regularization terms. Finally, numerical examples demonstrate the effectiveness of our algorithms.     

Low-Temperature Selective Catalytic Reduction of NO with NH<Subscript>3</Subscript> over Fe–Ce–O<Subscript><Emphasis Type="Italic">x</Emphasis></Subscript> Catalysts

In this study, we used a simple impregnation method to prepare Fe–Ce–O _x catalysts and tested them regarding their low-temperature (200–300 °C) selective catalytic reduction (SCR) of NO using NH₃. We investigated the effects of Fe/Ce molar ratio, the gas hourly space velocity (GHSV), the stability and SO₂/H₂O resistance of the catalysts. The results showed that the FeCe(1:6)O _x (Ce/Fe molar ratio is 1:6) catalyst, which has some ordered parallel channels, exhibited good SCR performance. The FeCe(1:6)O _x catalyst had the highest NO conversion with an activity of 94–99% at temperatures between 200 and 300 °C at a space velocity of 28,800 h^?1. The NO conversion for the FeCe(1:6)O _x catalyst also reached 80–98% between 200 and 300 °C at a space velocity of 204,000 h^?1. In addition, the FeCe(1:6)O _x catalyst demonstrated good stability in a 10-h SCR reaction at 200–300 °C. Even in the presence of SO₂ and H₂O, the FeCe(1:6)O _x catalyst exhibited good SCR performance.     

Characterization of β-glucosidase from <Emphasis Type="Italic">Aspergillus terreus</Emphasis> and its application in the hydrolysis of soybean isoflavones

An extracellular β-glucosidase produced by Aspergillus terreus was identified, purified, characterized and was tested for the hydrolysis of soybean isoflavone. Matrix-assisted laser desorption/ionization with tandem time-of-flight/time-of-flight mass spectrometry (MALDI-TOF/TOF MS) revealed the protein to be a member of the glycosyl hydrolase family 3 with an apparent molecular mass of about 120 kDa. The purified β-glucosidase showed optimal activity at pH 5.0 and 65 °C and was very stable at 50 °C. Moreover, the enzyme exhibited good stability over pH 3.0–8.0 and possessed high tolerance towards pepsin and trypsin. The kinetic parameters K_m (apparent Michaelis-Menten constant) and V_max (maximal reaction velocity) for p-nitrophenyl-β-d-glucopyranoside (pNPG) were 1.73 mmol/L and 42.37 U/mg, respectively. The K_m and V_max for cellobiose were 4.11 mmol/L and 5.7 U/mg, respectively. The enzyme efficiently converted isoflavone glycosides to aglycones, with a hydrolysis rate of 95.8% for daidzin, 86.7% for genistin, and 72.1% for glycitin. Meanwhile, the productivities were 1.14 mmol/(L·h) for daidzein, 0.72 mmol/(L·h) for genistein, and 0.19 mmol/(L·h) for glycitein. This is the first report on the application of A. terreus β-glucosidase for converting isoflavone glycosides to their aglycones in soybean products.     

An empirical study of students’ understanding of a logical structure in the definition of limit via the <Emphasis Type="Italic">ε</Emphasis>-strip activity

This study explored students’ understanding of a logical structure in defining the limit of a sequence, focusing on the relationship between ε and N. The subjects of this study were college students who had already encountered the concept of limit but did not have any experience with rigorous proofs using the ε–N definition. This study suggested two statements, each of which is written by using a relationship between ε and N, similar to the ε–N definition. By analyzing the students’ responses to the validity of the statements as definitions of the limit of a sequence, students’ understanding of such a relationship was classified into five major categories. This paper discusses some essential components that students must conceptualize in order properly to understand the relationship between ε and N in defining the limit of a sequence.     

Do Human‐Figure Drawings of Children and Adolescents Mirror their Cognitive Style and Self‐Esteem?

The investigation probed relationships among human‐figure drawing, field‐dependent‐independent cognitive style and self‐esteem of 10–15 year olds. It also attempted to predict human‐figure drawing scores of participants based on their field‐dependence‐independence and self‐esteem. Area, stratified and multi‐stage random sampling were used to select a sample of 600 10–15 year olds residing in Kolkata city, India. The sample comprised three age‐based strata: 10 and 11 year olds; 12 and 13 year olds; and 14 and 15 year olds. Each stratum comprised 100 girls and 100 boys. Participants’ actual age‐ranges were 10 years 1 month – 11 years 10 months (first stratum); 12 years 4 months – 13 years 10 months (second stratum); and 14 years 3 months – 15 years 9 months (third stratum). Goodenough‐Harris Drawing Test, Group Embedded Figures Test and Coopersmith Inventory were administered for assessing participants’ human‐figure drawing, field‐dependence‐independence and self‐esteem respectively. Results revealed significant positive relations among pertinent variables. Participants’ human‐figure drawing scores could be significantly predicted by their field‐dependence‐independence and self‐esteem.     

Every child matters? An evaluation of “Special Educational Needs” programmes in England

The need for education to help every child has become more important for policy in the US and the UK. Remedial programmes are often difficult to evaluate because participation is usually based on pupil characteristics that are largely unobservable to the analyst. We evaluate programmes for children with ‘Special Educational Needs’ in England. We show that the decentralized design of the policy generates much stronger differences across schools in access to remediation resources for children with moderate learning difficulties than for children with either no difficulties or severe difficulties. However, these differences are not reflected in subsequent educational attainment – suggesting that the programme is ineffective for children with moderate learning difficulties. Also, we use demographic variation within schools to consider the effect of the programme on whole year groups. Our analysis is consistent with no overall effect on account of the combined direct and indirect (spillover) effects.